Fuze powder composition



Ufli td States FUZE POWDER COMPOSITION David Hart, Dover, 'N. J.

-Noi)rawing. Application February 6, 1950, Serial N0. 142,721

20 Claims. (Cl. 52-2 (Granted under Title 35, U.- s. Code(1952), sec. 2 66) The-invention herein described and claimed, if pat- -ented,-may be manufactured and used by -or for .--the Government of the United Statesfor governmental pur- .-pses without the'paymentto'me of any royalty thereon.

The present invention'relat'e's to new and substantially non-gaseous powder composition intended for use in powder trains'of ammunition to provide a definite burning time interval. Particularly, the invention reside's'in the use of dichromated zirconium-nickel-alloy powders -and titanium-nickel 'alloy powders, together with potassium perchlorate and barium-Chromateto produce "the and elevated temperatures up to 1 70 Fs-over longperiods of time.

Practically all non-gaseous fuze powders presently employed, increase in burning time when stored at normal and elevated temperatures up to 170 F. This is generally due to the slow-oxidation of the metal or alloys employed. In 1947, alloys of zirconium-nickel and titanium-nickel in powdered form first became available commercially. I have discovered that the employment of dichromated Zirconium-nickel and titanium-nickel alloy powders, together with potassium perchlorate and barium chromate, each in a very finely divided state, produces a fuze powder composition which meets each and all of the requirements indicated above.

As examples, the following compositions have been particularly successful in producing easily ignitable, uniform burning, non-gaseous fuze powders of definite burning time intervals, which will burn through at temperatures between 65 F. and +l70 F. and which will not change appreciably in burning time after storage at +170 F. over long periods of time.

' wiz, dichromated "zirconium-nickel"alloy, dichrornated titanium-nickel alloy, potassium perchlorate and barium chromate, theburning rates ofthe desired cornpositions may-be varied over a wide range. The'burning rates 5 may also-be varied widelyby varying the proportions of 5 zirconium to nickel or titanium to nickel in the alloys. In compositions prepared according to the present invention containing dichromated zirconium-nickelalloys, Y the dichromated zirconium-nickel alloy may varyyfor example, from 10 to 35 percent, the-potassiumperchloirate-from 2 to ZOpercent and the barium'chromate from '50 to 85iperce'ntn The zirconium in the zirconium-nickel valloys may vary, for example, from '30 to 70-percent. More or less -similar-wide variations -may be =made in the proportions of the ingredients of the compositions -c0ntaining dichromated titanium-nickel alloys, theipro- 1 portion of each'ingr'edient and the-composition of the alloy being chosen accordingto theburning'r'ate' desired. These new fuzei powder compositions are very "readily (prepared, but carefulcontrol of the-particle size of the -i'ng'redients is essential. It is desirable that all of tthe -ingredients be finely divided so as topass-thr'ough a 250 mesh screen. The powdered ZlICOIllliflPlllCkCl alloy and the powdered titanium-nickel alloy is dichromated by --immersing it in an aqueous solution of l to 20 percent sodium dichromate containing less than onepercent of an-alkali acid sulfate, boiling for /2 hour, filtering and drying at 100 C. Dry incorporation of the fuze powder ingredients may be used, but it is preferable to wet mix the compositions using water or alcohol. After thorough incorporation, the fuze powders are granulated in commercially available mechanical .granulators or -by passing through screens. Although bindingagents have not been found necessary to assist in 'granulating and 1 pelletingthese powders, on'e'maybe used if'sp'ecialcases require 'it. p v

Having thus described the'invention, what'is claimed as new is:

l. A fuze powder composed of a mixture containing 40 10 to 35 percent finely divided dichromated zirconiumnickel alloys, 2 to 20 percent potassium perchlorate and 50 to 85 percent barium chromate.

2. A fuze powder composed of a mixture of about 10 to 35 percent dichromated zirconium-nickel alloys sufiiciently finely divided to pass through a 250 mesh screen, 2 to 20 percent potassium perchlorate and to 85 percent barium chromate, each sufficiently finely divided to pass through a 250 mesh screen.

3. A fuze powder composed of a mixture containing 5 dichromated titanium-nickel alloy powder, potassium perchlorate and barium chromate, each sufficiently finely divided to pass through a 250 mesh screen.

4. The fuze powder of claim 2 in which the alloy of zirconium-nickel contains from 30 to 70% Zirconium. 5. The fuze powder of claim 2 containing additionally about 3% of an organic binder.

- Burning g gg gi 213 ;58 Potassium Barium Rate 001- No coniurn- Titanium- Perchlo' Chromate Binder (Percent) Nickel Nickel rate (Per- (Percent) longl x 0.2"

(Percent) (Percent) cent) g fff It is not intended that this invention be limited to the specific examples set forth above, as it is known that by varying the proportions of the combining ingredients,

6. The fuze powder of claim 5 in which the organic binder is ethyl cellulose.

7. A fuze powder containing from 10 to 35% of a member of the group consisting of dichromated zirconium-nickel and titanium-nickel alloys, the remainder of said powder consisting substantially of inorganic oxidizing agents. v

8. The fuze powder of claim 7 in which the alloy of zirconium-nickel contains from 30 to 70% zirconium.

9. The fuze powder of claim 7 in which the alloy of titanium-nickel contains from 30 to 70% titanium.

10. The fuze powder of claim 7 in which the inorganic oxidizing agents are chosen from the class consisting of potassium perchlorate and barium chromate.

11. A stable non-gaseous fuze powder composition comprising a major proportion of an inorganic oxidizing agent and a minor proportion of a component selected from the group consisting of di-chromated zirconiumnickel alloy powder, dichromated titanium-nickel alloy powder, and mixtures of dichromated zirconium-nickel alloy powder and dichromated titanium-nickel alloy powder.

12. A stable, non-gaseous fuze powder composition comprising a major proportion of an inorganic oxidizing agent and a minor proportion of a component consisting of dichromated zirconium-nickel alloy powder.

13. A stable, non-gaseous fuze powder composition comprising a major proportion of an inorganic oxidizing agent and a minor proportion of a component consisting of dichromated titanium-nickel alloypowder.

14. A stable, non-gaseous fuze powder composition comprising a major proportion of an inorganic oxidizing agent and a minor proportion of a component consisting of a mixture of dichromated zirconitm1-nickel alloy powder and titanium-nickel alloy powder.

15. A stable non-gaseous fuze powder composition comprising a major proportion of a mixture of potassium perchlorate and barium chromate, and a minor proportion of a component selected from the group consisting of dichromated zirconium-nickel alloy powder, dichromated titanium-nickel alloy powder, and mixtures of dichromated zirconium-nickel alloy powder, and dichromated titanium-nickel alloy powder.

16. The method of preparing a stable non-gaseous fuze powder composition which comprises treating an alloy powder selected from the group consisting of zirconium-nickel alloy powder, titanium-nickel alloy powder, with an aqueous solution of sodium dichromate, whereby a dichromated alloy powder is produced, and incorporating with said dichromated alloy powder, a major proportion of an inorganic oxidizing agent.

17. The method of preparing a stable non-gaseous fuze powder composition which comprises immersing an alloy powder selected from the group consisting of zirconium-nickel alloy powder, and titanium-nickel alloy powder, in an aqueous solution containing 1 to 20 per cent sodium dichromate, boiling said solution while said alloy powder is immersed therein, whereby a dichromated alloy powder is produced, and incorporating with said dichromated alloy powder, a major proportion of an inorganic oxidizing agent.

18. The method according to claim 16 wherein said aqueous solution of sodium dichromate contains 1 to 20 per cent sodium dichromate and less than 1 per cent of an alkali acid sulfate.

19. The method according to claim 16 wherein the incorporation of said dichromated alloy powder with said inorganic oxidizing agent is effected in the presence of a wetting material selected from the group consisting of alcohol and water.

20. The method according to claim 16 wherein after the incorporation with said dichromated alloy powder of an inorganic oxidizing agent the resulting mixture is subjected to a granulation operation.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A FUZE POWDER COMPOSED OF A MIXTURE CONTAINING 10 TO 35 PERCENT FINELY DIVIDED DICHROMATED ZIRCONIUMNICKEL ALLOYS, 2 TO 20 PERCENT POTASSIUM PERCHLORATE AND 50 TO 85 PERCENT BARIUM CHROMATE. 